Phytophthora pluvialis pest report

Publication Date

Thu, 02 Dec 2021, 13:13

Last Updated

Dec. 2, 2021, 1:13 p.m.

Report Number

GBR-39/1

Country

United Kingdom

Pest Id

Phytophthora pluvialis - (PHYTUV)

Report Status

Final

Hosts

Western hemlock (Tsuga heterophylla) Douglas fir (Pseudotsuga menziesii)

Pest Status (ISPM 8 - 2021)

• Present: not widely distributed and under official control

Geographical Distribution

Limited distribution – first found in a woodland site in Cornwall, England, UK.

Summary

As part of the surveillance programme for Phytopthora ramorum, aerial survey flights undertaken in late August identified a stand of western hemlock in Cornwall which appeared to be expressing very characteristic symptoms of this pathogen on a significant scale. Although western hemlock is a known host, disease expression on this scale and intensity has not previously been observed. Follow-up ground surveys by the Forestry Commission identified symptoms characteristic of Phytophthora and subsequent laboratory analysis confirmed Phytophthora pluvialis was present

Danger

Phytophthora pluvialis is reported to cause needle cast, shoot dieback, stem lesions, and has also been isolated from soil and rainwater. On the UK Plant Health Risk Register, the pathogen has a high unmitigated risk rating of 60, with a high likelihood of spread should it be introduced, and a high impact, particularly given the potential commercial value of trees at risk. A risk assessment has been done by the UK Plant Health Risk Group, which has concluded that Phytophthora pluvialis meets the criteria to be classified as a GB quarantine pest for regulatory purposes

Contact for info

[email protected]

Report files

Phytophthora pluvialis pest report

Website

https://www.gov.uk/guidance/phytophthora-pluvialis

Issue keywords

Commodity keywords